1. Field of the Invention
This application relates to a method and apparatus for processing telephone calls in a telecommunications network. In particular, but not exclusively, the application relates to the delivery of enhanced telephony services for calls received on local telephone exchange switches.
2. Description of the Related Technology
Local telephone exchange switches deliver telephony services to residential and business customers, including a variety of functions that enable such customers to control the behavior of incoming and outgoing telephone calls; for example, call forwarding services, whereby the customer can request that calls to their telephone number be diverted to some other telephone number.
Some users of telephony services desire more sophisticated control over the behavior of telephone calls than is commonly provided by the majority of local telephone exchange switches that are deployed in the Public Switched Telephone Network (PSTN). An established technique for the delivery of such enhanced telephony services is to make use of a capability that is offered by some local telephone exchange switches known as Advanced Intelligent Network (AIN). By means of AIN, calls to specific numbers served by the local telephone exchange switch can trigger a query that is sent to an external computing system, and the response provided by this computing system can be interpreted by the local telephone exchange switch so as to determine how to treat the call. Commonly, the call is re-directed to another system which provides the means to play announcements, collect digits dialed by the caller, re-direct the call to the originally-called number or to some other destination, release the call, etc.
Some existing local telephone exchange switches do not provide the ability to generate at least some types of AIN queries that are triggered by incoming or outgoing calls. It would therefore be desirable to provide techniques whereby a wide range of enhanced telephony services can be delivered to customers connected to such existing local telephone exchange switches.